Closure device for fuel tanks



June 13, 1967 DE LACY F. FERRIS CLOSURE DEVICE FOR FUEL TANKS Filed Jan. 27, 1966 30 FIG.I

United States Patent Office 3,3Zfi47 Patented June 13, 1967 3,325,047 CLOSURE DEVICE FOR FUEL TANKS De Lacy F. Ferris, Sepulveda, Califi, assignor, by mesne assignments, to the United States of America as represented by the Secretary of the Army Filed Jan. 27, 1966, Ser. No. 523,475 4 Claims. (Cl. 220--89) This invention relates to closure devices and more particularly to a quick-opening, rupturable closure device for the outlet of a fuel system tank.

It is desirable to hermetically seal packaged, liquid, rocket propellant tanks with a closure device which will resist high pressures during storage and transportation but which will quickly open at low pressures when the tanks are pressurized and the rockets started. Moreover, it is desirable that a closure device of the type described be simple and compact in construction and readily operable from a closed, completely sealed position in the tank outlet to a fully open position therewith.

Prior to the present invention, when the fuel tank is to be stored or transported, it has been conventional to locate a closure device including a wall-to-wal-l, shearable burst diaphragm of thin sheet metal within or across the tank outlet, the diaphragm being scored or coined circumferentially and supported by a support element which extends across the tank outlet from one side thereof to the other. In an arrangement of this type, in order to unsupport the burst diaphragm, it is necessary that the supporting element be moved a distance greater than the diameter of the tank outlet and the score pattern. In this prior structure, a relatively large support element is required since the latter element bridges the entire diameter of the tank outlet and, additionally, carries the load as a beam. This arrangement has the further disadvantage of requiring considerable space axially, thus, reducing the effective axial length of the tank.

Accordingly, in view of the foregoing, the primary object of the present invention is to provide a closure device for use in the outlet passage of a fluid propellant tank which device is highly effective for sealing the tank against high pressures but capable of rapidly opening the passage to flow when desired.

Another object of the invention is to provide a closure device which may be activated between closed and open positions by remote control means.

A further object of the invention is to provide a tank closure device which is relatively short in axial length to allow the effective axial length of the tank to be relatively longer.

A still further object of the invention is to provide a tank closure device utilizing a rupturable diaphragm which device prevents ruptured pieces from going downstream when the closure device is moved to open position.

An important feature of the invention resides in the provision of a burst diaphragm type hermetic sealing element disposed across the flow passage and formed with score marks which may be ruptured at the instant the closure is opened or at a predetermined time thereafter.

Another feature of the present invention resides in the provision, in a closure device, of a burst diaphragm support structure which is subject to shear, rather than compressive, loads.

Further objects, features, and advantages of this invention will be apparent from the following, detailed description and the accompanying drawing, wherein:

FIGURE 1 is an elevational, cross-sectional view of the tank outlet and closure device therefor illustrating the closure device in closed position within the tank outlet;

FIGURE 2 is a sectional view taken on line 2-2 of FIGURE 1 but having parts broken away and the burst diaphragm removed, this view depicting the score pattern in phantom; and

FIGURE 3 is a detailed view of a portion of FIGURE 2, this view having parts broken away and illustrating the relationship of the parts of the closure device when the device is in an open position, this view being taken looking in a direction from inside the tank axially outwardly thereof.

Referring now in detail to the drawing, wherein like reference numerals designate corresponding parts in the several views, reference numeral 2 designates a cylindrical outlet body of a fuel tank or the like fluid container (not shown). Outlet body 2 defines a cylindrical flow passage 4 whereby fuel may flow axially outwardly, in a downstream direction as indicated by the directional arrow in FIGURE 1. An annular groove 6 is formed in the downstream portion of the outlet body. A protrusion 10 extends radially from a portion of the outer circumference of outlet body 2 and is provided with an axial 'bore 12 opening at its inner end into groove 6 and passage 4.

A closure device, indicated generally at 20 (FIGURE 1), is provided to close outlet opening 4 during transportation and storage of the fuel tank. Closure device 20 includes a cylindrical burst diaphragm 22, which is secured as by welding about peripheral portion '24 within passage 4. The burst diaphragm, which is preferably formed of sheet metal, hermetically seals the outlet passage against flow outwardly thereof during storage and transportation. The burst diaphragm is provided with a substantially annular score mark 26 (shown in phantom in FIGURE 2). An unscored portion or sector 28 (FIGURE 3) extends radially from annular score mark 26 and functions as a hinge for the diaphragm when the diaphragm is ruptured along the score mark.

To support the diaphragm and prevent the same from rupturing during storage and transportation, a support assembly indicated generally at 30 is provided downstream of the burst diaphragm. Support assembly 30 includes a support latch 44, an undulated spring 32 and a plurality of support beams 36 (FIGURE 2). Support latch member 44, which is slida-bly disposed in bore 12, is provided at the inner end thereof with a support ledge 46 facing upstream and at the opposite end thereof with a connecting pin 48 extending therethrough for connection with a suitable operating lever 50. Spring 32 is positioned in annu lar groove 6 with edge portions of the downstream side thereof resting for support on base portion 8 of annular groove '6. As illustrated in the drawing (FIGURES 2 and 3), the spring has a series of undulations alternately facing radially inwardly and outwardly with generally radially extending connecting portions 34 being disposed for supporting the outer end 40 of each support beam 36. Each of the support beams is provided on outer end 40 with laterally extending ears or lugs 42 adapted to be supported (FIGURE 2) on support portions 34 of spring 32. The inner end 38 of each beam is supported (FIG- URE 2) on support ledge 46 of latch member 44.

To assemble the closure device within tank outlet body 2, the burst diaphragm is secured therein; the spring is positioned concentrically within annular groove 6; the support beams are positioned downstream of the burst diaphragm; and latch member 44 is moved to a position whereby the inner end of each beam is supported on ledge 46. In the closed position (FIGURES l and 2) a relatively large area of the burst ddiaphragm is effectively supported by beams 36 and latch 44.

In operation of the closure device from a closed position (FIGURE 1) to an open position (FIGURE 3), latch 44 is slidably withdrawn by any suitable operating means 50, thus, unsupporting the inner end of beams 36. A sudden application of pressure to the tank or upstream side of burst diaphragm 22 causes the diaphragm to stretch in a downstream direction until it tears along score pattern 26. Accordingly, the burst diaphragm ruptures along the score mark and is thrown by the force of the fuel downstream against the passage wall. Unscored diaphragm portion 28 functions like a hinge allowing the ruptured, central portion of the diaphragm to swing downstream. The beams will be rotated over center (FIGURE 3) against the springs and will assume a new position fiat against the wall of passage 4. Since the width of each beam adjacent ears 42 is slightly greater than the distance between adjacent support portions 34 of the spring, the opposite side portions of each beam adjacent the ears will be frictionally engaged between an adjacent pair of spring portions 34. Thus, the beams will be held in this position and prevented from being carried downstream. In addition, when the beams rotate to the open position shown in FIGURE 3, the radially inwardly facing shoulder 43 of each ear 42 rests for support on the upstream edge of spring 32. A small ruptured portion 26 and unscored portion 28 of the diaphragm is depicted in FIGURE 3. It should be apparent that substantially free flow is allowed through passage 4 when the device is in the open position (FIGURE 3); and unscored portion 28 of the diaphragm will prevent the diaphragm from being carried downstream by the force of the flowing fuel.

While the foregoing describes the burst diaphragm as being ruptured simultaneously with application of increased pressure on the upstream side of the diaphragm and withdrawal of the latch member, it should be apparent that the diaphragm and its score pattern could be designed so that rupture of the diaphragm may be effected by application of pressure at a predetermined time after withdrawal of the latch member. Moreover, while the closure device is described herein as being positioned within a tank outlet, it should be apparent that the device is adapted for use with other fluid flow passages. For example, the device of FIGURE 1 could be formed as a separable attachment unit including a cylindrical body having means for attachment at its upstream end to the opening of a tank outlet or the like flow passage.

Accordingly, a closure device is provided which is simple in construction and operation, yet highly effective for hermetically sealing the outlet passage of a fuel tank. The closure device is adapted for rapid operation between open and closed positions and may be operated remotely.

It should be understood that the specific embodiment of the invention described herein is merely illustrative of the principles of the invention and that various changes and modifications may be made without departing from the spirit and scope of the invention as set forth in the appended claims.

What is claimed is:

1. A closure device for hermetically sealing the outlet flow passage of a tank comprising, in combination: a tubular tank outlet body defining an axially extending flow passage and having an annular groove formed in the interior wall thereof, a protrusion extending radially outwardly from a peripheral portion of the exterior of said body, said protrusion having an axial bore extending therethrough and opening on its inner end into said annular groove; a generally cylindrical burst diaphragm secured about its peripheral edge to the interior wall of said outlet flow passage at a location axially inward of said annular groove, said diaphragm having a score pattern formed therein, said score pattern including a substantially circular frangible line concentric with but spaced radially inwardly from said peripheral diaphragm edge; and support means disposed transversely across said fiow passage for supporting said burst diaphragm, said support means including a spring member disposed in said annular groove and a latch member slidably disposed in said axial bore for moving the support means from a supporting position to an unsupporting position whereby the closure device opens the flow passage permitting flow axially outwardly of the tank.

2. A closure device as defined in claim 1, wherein said support means includes a plurality of elongated, plate-like support beams radially disposed across said flow passage in supporting engagement with the axially outwardly facing side of said diaphragm, each said beam having a radially inner end and a radially outer end; said spring member being defined by an undulated spring positioned concentrically of the passage within said annular groove; and said latch member having a supporting ledge formed on the inner end thereof, whereby the outer end of each said beam is supported on a portion of said spring and the inner end of each said beam is supported on said supporting ledge.

3. A closure device as defined in claim 2 wherein each said beam is formed on its outer end with a pair of laterally extending ears and said spring includes generally radial ly extending, spaced-apart support portions, whereby said ears of each beam rest on adjacent, said support portions of the spring.

4. A closure device as defined in claim 3 wherein the width of each beam adjacent the ears is slightly greater than the spacing between adjacent spring support portions, whereby, upon withdrawal of the latch unsupporting the inner ends of the beams, said beams will swing axially outwardly int-o engagement with the inner wall of said tubular body, and the portion of the beams adjacent the ears will frictionally engage adjaecnt spring support portions.

No references cited.

THERON E. CONDON, Primary Examiner.

R. A. SCHWARTZ, Assistant Examiner. 

1. A CLOSURE DEVICE FOR HERMETICALLY SEALING THE OUTLET FLOW PASSAGE OF A TANK COMPRISING, IN COMBINATION: A TUBULAR TANK OUTLET BODY DEFINING AN AXIALLY EXTENDING FLOW PASSAGE AND HAVING AN ANNULAR GROOVE FORMED IN THE INTERIOR WALL THEREOF, A PROTRUSION EXTENDING RADIALLY OUTWARDLY FROM A PERIPHERAL PORTION OF THE EXTERIOR OF SAID BODY, SAID PROTRUSION HAVING AN AXIAL BORE EXTENDING THERETHROUGH AND OPENING ON ITS INNER END INTO SAID ANNULAR GROOVE; A GENERALLY CYLINDRICAL BURST DIAPHRAGM SECURED ABOUT ITS PERIPHERAL EDGE TO THE INTERIOR WALL OF SAID OUTLET FLOW PASSAGE AT A LOCATION AXIALLY INWARD OF SAID ANNULAR GROOVE, SAID DIAPHRAGM HAVING A SCORE PATTERN FORMED THEREIN, SAID SCORE PATTERN INCLUDING A SUBSTANTIALLY CIRCULAR FRANGIBLE LINE CONCENTRIC WITH BUT SPACED RADIALLY INWARDLY FROM SAID PERIPHERAL DIAPHRAGM EDGE; AND SUPPORT MEANS DISPOSED TRANSVERSELY ACROSS SAID FLOW PASSAGE FOR SUPPORTING SAID BURST DIAPHRAGM, SAID SUPPORT MEANS INCLUDING A SPRING MEMBER DISPOSED IN SAID ANNULAR GROOVE AND A LATCH MEMBER SLIDABLY DISPOSED IN SAID AXIAL BORE FOR MOVING THE SUPPORT MEANS FROM A SUPPORTING POSITION TO AN UNSUPPORTING POSITION WHEREBY THE CLOSURE DEVICE OPENS THE FLOW PASSAGE PERMITTING FLOW AXIALLY OUTWARDLY OF THE TANK. 